You might want to surprise her with the perfect Valentine's Day gift, but how do you protect yourself when buying jewelry.

Don't get duped into buying a dud. Whether you're eyeing baubles at brand name boutiques or bulk big box stores, a little knowledge can save you big.

"Be prepared, get some knowledge online before you come in," Angelo Palmieri said.

It's the golden rule from Angelo and his dad, Don. They run the Gem Certification and Assurance lab in Manhattan's diamond district.

Tip #1: educate yourself on what jewelry costs.

"You should have an idea and you see price that's too high or too low you should raise on eyebrow," Angelo said.

Tip #2 Beware Prices Too Good to Be True

Prices too good to be true usually are, but if you're on a budget don't "dis" cheaper precious stones or metals that are inexpensive yet very "IN" especially for him, like Silver, Tungsten or Titanium.

"These are very pleasing to the eye. They're light, inexpensive and men don't care for their jewelry as most women do as we know. If you lose on it, more affordable to replace it," Angelo said.

How affordable? One ring in titanium costs $80. In gold, it could cost up to a thousand dollars.

Tip # 3 Look for Metal markings

If you are going for the gold, look for markings like a trademark: who made it and hallmarks indicating 14, 18 or the yellowest, pure, 24 k karat gold.

Tip #4 Diamond vs. CZ

Just because something looks like the real deal doesn't mean it is.

Even to the trained eye, it is tough to tell between a high quality diamond and a good cubic zirconia, but the price difference is huge.

A diamond could be worth $15,000 while a CZ in the same size could be worth about $20.

#5 Know Your Jeweler's Reputation

That's why it's so important to buy from someone you trust, and don't just read reviews.

"With Valentine's Day coming up you really want to be careful," Angelo said. "You want to know the jeweler you are buying from. Get recommendations from family friends and coworkers."

#6 Read Return Policy

Before your purchase go over the shop's return policies very carefully. Most sellers have a 30 day return window, get it in writing.

#7 Get an Independent Appraisal

Another thing to always get is an independent appraisal, ensuring you bought the real deal and can enjoy your investment.

"Gold and diamonds never go out of style. They've been popular since jewelry's been sold," Angelo said.

Other big tip-offs to rip off include the Breath Test: Real diamonds don't fog up if you blow on them.

75 % off sales means the items are marked way high for Valentine's Day. Be wary.